Abstract Advanced oxidation processes (AOPs) are regarded as one of the most promising technologies for VOC degradation. In this study, MnO2-rGO composite samples were prepared and applied in a system consisting of VUV photolysis and ozone catalytic oxidation for the degradation of toluene. Extensive characterizations, including BET, SEM, TEM, HRTEM, Raman, XRD, FTIR and XPS, were conducted to analyze the features of the composite MnO2-rGO samples. Results of toluene removal, mineralization and ozone decomposition showed that the MnO2-rGO composite sample with Mn loading of 25 wt. % exhibited the best performance in this study due to its superior adsorption activity and moderated MnO2 loading. The intermediates of the degradation process were analyzed showing more by-products with shorter chains in the presence of the MnO2-rGO catalysts compared to VUV photolysis alone, indicating more complete reactions occurred. Generation of hydroxyl radicals (•OH) and superoxide radicals (•O2-) were confirmed to contribute in the toluene degradation. Two reaction pathways (i.e. •O2- and OH• based) and mechanism of toluene degradation were proposed.

中文翻译：

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真空紫外光解和臭氧催化氧化在MnO2-rGO复合催化剂上协同降解甲苯

摘要 高级氧化工艺（AOPs）被认为是最有前途的VOC降解技术之一。在本研究中，制备了 MnO2-rGO 复合材料样品，并将其应用于由 VUV 光解和臭氧催化氧化组成的用于降解甲苯的系统中。进行了广泛的表征，包括 BET、SEM、TEM、HRTEM、拉曼、XRD、FTIR 和 XPS，以分析复合 MnO2-rGO 样品的特征。甲苯去除、矿化和臭氧分解的结果表明，MnO2-rGO 复合样品的 Mn 负载量为 25 重量％。由于其优异的吸附活性和适度的 MnO2 负载，% 在本研究中表现出最佳性能。对降解过程的中间体进行了分析，表明与单独的 VUV 光解相比，在 MnO2-rGO 催化剂存在下，更多的副产物具有更短的链，表明发生了更完全的反应。羟基自由基 (•OH) 和超氧自由基 (•O2-) 的产生被证实有助于甲苯降解。提出了两种反应途径（即基于•O2-和OH•）和甲苯降解机理。